Domestic and foreign crawler type continuous mining machines are well known in the prior art. Some examples of the patented prior art are contained in U.S. Pat. Nos. 3,899,212 and 3,972,429.
The broad objective of the present invention is to provide a very low profile mining machine which is capable of moving into and throughout a mine fully assembled. Many present day mining machines, including imported machines, are so high when assembled that they have to be disassembled outside of a mine and transported, piece-by-piece, through the relatively low mine entrance passageway and reassembled in the mine tunnel. Some of the machines must be further disassembled and reassembled in order to move from one part of the mine to another. This is obviously a costly and laborious process, and it is the purpose of the present invention to substantially eliminate or greatly reduce this prior art problem.
Another important reason dictating the lowest possible height or profile overall for a mining machine is that increasingly shallow seams of coal and other minable solids are now being utilized, whereas in the past such shallow seams were ignored in the interest of mining much larger seams which have now been diminished to a great extent. It is therefore a question of economics which requires that mining machines be made increasingly lower and more compact without loss of stability, ruggedness and massiveness, which are essential requirements for a practical and efficient mining machine. More specifically, in explaining the desirability of a low profile mining machine, a mine entrance may measure four feet high by a mile or more long before reaching the main mine tunnel. In forming such an entranceway through hard rock in many cases, it is obviously much more economical to be able to minimize the height of the entranceway and this height will be determined by the height or profile of the mining machine which must form the passage and enter into the mine proper.
In essence, the present invention seeks to satisfy the above need of the art to a great extent, and the invention is believed to be a very significant advance in this respect over the prior art. Additionally, the low profile mining machine according to the invention loses none of its mobility, stability and massiveness because of its shape and possesses a mining boom which has a large swing and shear range during operation.
Other features and advantages of the invention will become apparent during the course of the following description.